Solvent dyeing copolyester fibers

ABSTRACT

A PROCESS FOR THE PREPARATION OF A DEEP-DYED POLYESTER FIBER WITH GOOD BULK AND HAND IN WHICH A POLYESTER FIBER DERIVED FROM ETHYLENE GLYCOL, DIMETHYL TEREPHTHALATE AND FROM ABOUT 1 TO ABOUT 15 WEIGHT PERCENT OF A DIFUNCTIONAL DYE OPENER HAS APPLIED TO IT A CHLORINATED HYDROCARBON COMPRISED OF FROM ABOUT 0.3 TO ABOUT 10 PERCENT (BY WEIGHT OF CHLORINATED HYDROCARBON) OF DISPERSE DYE AND FROM ABOUT 0.1 TO ABOUT 10 PERCENT (BY VOLUME OF CHLORINATED HYDROCARBON) OF WATER.

United States Patent 3,746,507 SOLVENT DYEING COPOLYESTER ERS Colin L. Browne, Charlotte, N.C., and Terry A. Brodof, Lincroft, N.J., assignors to Celanese Corporation, New York, N.Y. No Drawing. Filed June 29, 1971, Ser. No. 158,123 Int. Cl. D06!) 3/00 US. Cl. 8174 8 Claims ABSTRACT OF THE DISCLOSURE A process for the preparation of a deep-dyed polyester fiber with good bulk and hand in which a polyester fiber derived from ethylene glycol, dimethyl terephthalate and from about 1 to about 15 weight percent of a difunctional dye opener has applied to it a chlorinated hydrocarbon comprised of from about 0.3 to about 10 percent (by weight of chlorinated hydrocarbon) of disperse dye and from about 0.1 to about 10 percent (by volume of chlorinated hydrocarbon) of water.

There is provided a process for the preparation of a deep-dyed polyester fiber. In this process the polyester fiber (which is derived from ethylene glycol, dimethyl terephthalate, and from about 1 to about Weight percent of a difunctional dye opener) has applied to it a chlorinated hydrocarbon comprised of from about 0.3 to about 10 percent (by weight of chlorinated hydrocarbon) of disperse dye, and from about 0.1 to about 10 percent (by volume of chlorinated hydrocarbon) of water.

The dyed fiber of this invention has good bulk and hand and possesses good dye fastness and dye uniformity properties. The dye yield on said fiber is at least 85 percent.

This invention relates to the solvent dyeing of dyeopened polyester.

Solvent dyeing processes for synthetic fibers such as, e.g., polyester, are Well known to the art. With polyester fibers these processes suffer several disadvantages. Foremost among them are relatively poor dye yield (on the order of from about 50 to about 70 percent), dye uniformity, and dye fastness.

It is thus an object of this invention to provide a solvent dyeing process for polyester wherein the depth of dyeing, dye yield, dye uniformity, and dye fastness prop erties of the dyed fiber are improved. In accordance with this invention there is provided a process for the preparation of a deep-dyed polyester fiber with good bulk and hand, said polyester being derived from ethylene glycol, dimethyl terephthalate, and from about 1 to about 15 percent (by weight of dimethyl terephthalate) of a difunctional dye opener, comprising the step of applying to said fiber (1) a chlorinated hydrocarbon of 1 to about 4 carbon atoms comprised of from about 0.3 to about 10 percent (by weight of chlorinated hydrocarbons) of disperse dye and (2) from about 0.1 to about 10 percent (by volume of chlorinated hydrocarbon) of water; whereby a dyed polyester fiber with good dye fastness, good dye uniformity, and a dye-yield of at least 85 percent is obtained.

It has been discovered that the dye-opened copolyester fiber used in the process of this invention dyes significantly deeper than unmodified poly(ethylene terephthalate) and allows one to obtain a greater dye yield when the process of the instant invention is used. Said copolyester is derived from ethylene glycol, dimethyl terephthalate (or, when a direct esterification process is used, terephthalic acid), and from about 1 to about 15 percent (by weight of dimethyl terephthalate or terephthalic acid) of a difunctional dye opener. Some of the dye openers which may be used to prepare said copolyester are mentioned in a book by H. F. Mark et a1. entitled Man- Made Fibers Science and Technology, New York, Interscience, vol. 3, 1958 (cf. pp. 21-35). It is preferred that the difunctional dye opener be a dicarboxylic acid containing from 2 to about 18 carbon atoms such as, e.g., oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid, thaspic acid, isophthalic acid, phthalic acid, and the like. It is even more preferred that the dye opener be selected from the group consisting of isophthalic acid and adipic acid; and the most preferred dye opener is adipic acid.

Generally the copolyester fiber used in the process of this invention is derived from about 2 to about 10 percent (by weight of dimethyl terephthalate or terephthalic 'acid) of dye opener. The dye opener may be added to the ethylene glycol and dimethyl terephthalate (or terephthalic acid) reactants at the beginning of the ester-interchange (or direct esterification), during ester-interchange (or direct esterification), or after ester-interchange (or direct esterification); of course the dye opener must be added before polycondensation is complete. It is preferred to add the dye opener to the reaction mixture when the intrinsic viscosity of said mixture is at least 0.3. Intrinsic viscosity is a measure of the degree of polymerization and may be defined as wherein the relative viscosity, 1 is the viscosity of a dilute solution of the polymer in a solvent divided by the viscosity of the solvent per se measured in the same units at the same temperature; and C is the concentration in grams of the polymer per ml. of solution. Measurements may be made of relative viscosity (on an 8% solution of polyester in ortho-chlorophenol at 25 C.) and converted to intrinsic viscosity by an empirical formula. It is preferred that the polymers used in the process of this invention have an intrinsic viscosity of from 0.40 to about 0.95, although it is more preferred that they have an intrinsic viscosity of from about 0.40 to about 0.70, and it is most preferred that they have an intrinsic viscosity of about 0.6.

The copolyester fiber used in the process of this invention may also be comprised of dye site additives and/ or other copolymerizable dye-site agents, delustrants, flame retarding agents, etc. Up to about 15 percent (by weight of copolyester) of one or more of these other agents may comprise the copolyester.

The term fiber as used herein refers to fiber which may or may not be in the form of textile material. This term thus refers to filament yarn, staple, tow, fabric, etc.

In the process of the instant invention to the fiber of this invention is applied both a chlorinated hydrocarbon comprised of from about 0.3 to about 10 percent (by weight of chlorinated hydrocarbon) of disperse dye and from about 0.1 to about 10 percent (by volume of chlorinated hydrocarbon) of water. It is preferred that the chlorinated hydrocarbon be a chloroethylene, and the di, tri-, and perchloroethylene hydrocarbons work well in their process. Perchloroethylene is especially preferred for a number of reasons. It has a low specific heat and thus requires less energy than water to be heated up to a specific temperature. It has a relatively low heat of vaporization so that textile treated therewith dry relatively fast.

The chlorinated hydrocarbon used in the process of this invention is comprised of from about 0.3 to about 10 percent (by weight of chlorinated hydrocarbon) of disperse dye. It is preferred that the disperse dye comprise from about 0.5 to about 5 weight percent of the limit as C approaches 0 chlorinated hydrocarbon; it is most preferred that the dye comprise about 1.5 percent (by volume of the chlorinated hydrocarbon). Suitable disperse dyes which may be used in the process of this invention include, e.g.,

the disperse dyes described on pages 16551742 of 5 least one percent (based on volume of perchloroethylvolume 1 of the Colour Index (The American Associaene) of water. Thereafter the dyed fabrics were nnsed tion of Textile Chemists and Colorists, Lowell, Masss., in baths of cold perchloroethylene three times and dried. second edition, 1956). Thus, e.g., dyes such as Disperse Samples of unmodified poly(ethylene terephthalate and Red 1, Disperse Blue 60, Disperse Red 60, Disperse Blue poly(ethylene terephthalate) copolyester derived from 87, Disperse Blue 27, Disperse Red 88, Disperse Red 75, ethylene glycol, dimethyl terephthalate, and percent Disperse Yellow 42, Disperse Orange 30, Disperse Violet (by weight of dimethyl terephthalate) of adipic acid 35, Disperse Yellow 63, Disperse Black, and the like were dyed with various disperse dyes to determine the may be used in the process of this invention. A co-solvent relative depth of shade, contrast, fastness properties, and such as dimethyl acetamide or dimethylsulfoxide, e.g., variation of contrast with time. The relative contrast bemay be used to increase the solubility of the dye in the tween regular and dye-opened polyester is represented hl i t d h d b in the table shown below as a color distribution ratio In the process of the instant invention the aforemenwhere deep-dye polyester (the adipate copolymer) is tioned copolyester fiber has applied to it both the chlorigiven a rating of 10 and unmodified polyester is given nated hydrocarbon comprised of disperse dye and from a number representing the visual evaluation of the relaabout 0.1 to about 10 percent (by voume of chlorinated 2O tive amount of dye on the fiber. hydrocarbon) of Water. It is preferred to use from about 0.5 to about 2 percent of water (by volume), and it TABLE 1 is most preferred to use at least about 1 percent of water (by volume). The use of water in conjunction Example Dye gg gfii 53 3932 W1th the use of the aforementioned copolyester fiber helps 5 one achieve the Stated of this invention 51:33:13:1 35331 23tifiitdjjitjii: 13 l After said copolyester fiber has had said chlorinated 3 Disperse Red 60 1o 2 hydrocarbon comprised of dye and said water applied E33 3;: 18 l to it, it is preferred to fix the dye onto the fiber by 6- Disperse Red 33... 10 2 subjecting the fiber to a temperature of from about 80 g ggfig h i8 3 to about 250 degrees centigrade for from about 10 sec- 9- Disperse Orange 30 10 1 ends to about 10 minutes; one may use either hot air i9: gfigg gg Qfifiig: i8 fixation or hot solvent (such as perchloroethylene sol- 12. Disperse Black 10 2 vent) fixation techniques. It is preferred to fix the dye on the fiber by subjecting the fiber tohot perchloro- 5 ethylene vapor at a temperature of from about 120 to The fastness properties of the aforementioned dyes about 160 degrees centigrade for from about 0.5 to about are given below in Table 2 wherein A denotes un- 5 minutes; it is most preferred to use a perchloroethylmodified polyester, B denotes adipate copolyester, a ene vapor at a temperature of about 140 degrees centiis the dye used in Example 1, b" is the dye used in grade and subject the fiber to it for about 2 minutes. Example 2, c is the dye used in Example 3, etc.

TABLE 2 Shade Shade change, 120 change, dry 10 hrs. 20hrs. F. Wash test. Dry crocking Wet crocking cleaning A B A B A B A B A B A B The dye yields obtainable with the process of the present invention are relatively high, being at least 85 percent (and preferably at least 90 percent). Dye yield is a function of the amount of dye absorbed divided by the amount of dye applied.

In order to best illustrate their invention, applicants present the following examples which are not to be deemed limitative thereof. Unless otherwise stated all parts are by weight and all temperatures are in degrees centigrade.

EXAMPLES Examples 1-2 Unless otherwise specified, in these examples 15 grams of the disperse dye was boiled in 500 ml. of perchloroethylene under reflux for 5 minutes, and the solution was then filtered hot. The hot solution was then placed in the dyeing vessel and boiled under slight reflux. Fabrics were scoured before dyeing by dipping them into a bath The use of water in the process increased the dye-yield, improved the dye-uniformity, and improved fastness properties; it is preferred to use at least 1 percent of water (by volume of chlorinated hydrocarbon) in the process.

Examples 13-19 'Examples 20-26 In these Examples the general procedure of Examples 1-19 was followed, and the disperse dye was fixed onto the fabric by leading the fabric through perchloroethylene vapor at a temperature of 145 degrees centigrade for 60 seconds. The relative depth of shade obtained with unmodified polyester fabric and the adipate copolyester fabric was determined in accordance with the procedure of Examples 1-19. The results are shown in Table 4.

TAB LE 4 Adipate copolymer Example Dye polyester 20 Polysol Yellow GS- 24 25 Polysol Blue GS The disperse dye may be a solution or dispersion in the chlorinated hydrocarbon. It is preferred that it be in the form of a dispersion and that, if need be, the chlorinated hydrocarbon be comprised of a suitable surfactant. Surfactants which may be used include, e.g., long chain fatty acids of from about 12 to about 18 carbon atoms.

Although the above examples and descriptions of this invention have been very specifically illustrated, many other modifications will suggest themselves to those skilled in the art upon a reading of this disclosure. These are intended to be comprehended within the scope of this invention.

What is claimed is:

1. A process for the preparation of a deep-dyed polyester fiber with 'good bulk and hand, said polyester being derived from ethylene glycol, dimethyl terephthalate, and from about 1 to about 15 percent (by weight of dimethyl terephthalate) of a dicarboxylic acid selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pinelic acd, suberic acid, axelic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid, thaspic acid, isophthalic acid and phthalic acid, comprising the step of applying to said fiber (a) a chlorinated hydrocarbon of 1 to about 4 carbon atoms comprised of from about 0.3 to about percent (by weight of chlorinated hydrocarbon) of disperse dye and (b) from about 0.1 to about 10 percent (by volume of chlorinated hydrocarbon) of water; whereby a dyed polyester fiber with good dye fastness, good dye uniformity, and a dye-yield of at least 85 percent is obtained.

2. The process of claim 1, wherein:

(a) said chlorinated hydrocarbon is perchloroethylene;

(b) from about 0.5 to 2 percent of water (by volume of perchloroethylene) is applied to said fiber; and

(c) after "said perchloroethylene comprised of disperse dye and said water is applied to said fiber, said dye is fixed onto said fiber by subjecting said fiber to a temperature of from about 8-0 to about 250 degrees centigrade for from about 10 seconds to about 10 minutes.

3. The process of claim 2, wherein said dye is fixed onto said fiber by subjecting said fiber to hot air at a temperature of from about to about 250 degrees centigrade.

4. The process of claim 2, wherein said dye is fixed onto said fiber by subjecting said fiber to hot perchloroethylene vapor at a temperature of from about to about 250 degrees centigrade.

5. The process of claim 4, wherein:

said perchloroethylene solution is comprised of from about 0.5 to about 5 percent (by weight of perchloroethylene) of disperse dye, said dye forming a solvent dispersion in the perchloroethylene. 6. The process of claim 5, wherein after said perchloroethylene comprised of said dye and said water is applied to said fiber the dye is fixed onto said fiber by subjecting said fiber to a temperature of from about to about 160 degrees centigrade for from about 0.5 to about 5 minutes.

7. The process of claim 6, wherein said dicarboxylic acid dye opener is selected from the group consisting of adipic acid and isophthalic acid; and said polyester is derived from ethylene glycol, dimethyl terephthalate, and from about 2 to about 10 percent (by weight of dimethyl terephthalate) of dye opener. 8. The process of claim 7, wherein: (a) said dye opener is adipic acid; (b) said polyester is derived from ethylene glycol, dimethyl terephthalate, and about 8.weight percent (by weight of dimethyl terephthalate) of adipic acid;

(0) said perchloroethylene is comprised of about 1.5 percent (by weight of perchloroethylene) of disperse dye, and the perchloroethylene and at least about 1 percent (by volume of perchloroethylene) of water are applied to the fiber prior to the time the dye is fixed onto the fiber; and

((1) said disperse dye is fixed onto said fiber by subjecting said fiber to hot perchloroethylene vapor at a temperature of about degrees centigrade for about 2 minutes.

References Cited UNITED STATES PATENTS 3,199,281 8/1965 Maerov 57140 FOREIGN PATENTS 1,192,984 5/1970 Great Britain 8-174 OTHER REFERENCES White: American Dyestufi Rep., July 31, 1967, pp. 591-597.

DONALD LEVY, Primary Examiner US. Cl. X.R. 8176 

